FR3068031A1 - GLAZING WITH ANTISOLAR PROPERTIES COMPRISING A TITANIUM OXYNITRIDE LAYER - Google Patents

Abstract

The invention relates to an antisolar glass article comprising at least one glass substrate and a stack of layers deposited on at least one face of said substrate, said layer stack comprising a titanium oxynitride layer of general formula TiNxOy, in which which 1.00 <x <1.20 and wherein 0.01 <y <0.10, said stack of layers being further constituted by layers of dielectric materials and optionally metal or nitride layers based on chromium, nickel , titanium, niobium or a mixture of at least two of these elements.

Description

GLAZING WITH SUN-PROOF PROPERTIES COMPRISING A LAYER

OF TITANIUM OXYNITRIDE The invention is relates to the domain of the substrates or glassware, glazing type of buildings or

automobiles, comprising on their surface coatings of the thin layer type giving them sunscreen and low-emissivity properties. By glazing is meant in the sense of the present invention any glass product consisting of one or more glass substrates, in particular single glazing, double glazing, triple glazing, etc. The present invention relates in particular to laminated glazing comprising at least two glass substrates linked together by a layer of plastic material such as PVB (polyvinyl butyral) or PU (polyurethane). By sunscreen is understood in the sense of the present invention the ability of glazing to limit the energy flow, in particular infrared radiation (IR), passing through from the outside to the inside of the house or passenger compartment, while retaining a light transmission allowing vision at least from the inside to the outside of the building or the cabin it equips. Preferably, the glazings according to the invention have a high light transmission, that is to say typically greater than 20, or even greater than 25, or even greater than 30, or even even greater than 40 or even greater than 50%.

By low-emissive stack is meant stacks incorporating at least one functional layer operating essentially in the mode of reflection of a major part of the average IR (infrared) radiation.

Such glazing provided with stacks of thin layers thus act on the incident solar radiation and allow solar protection and / or thermal insulation of the passenger compartment or the dwelling. In addition, these coatings must be aesthetically pleasing, that is to say that they must have a colorimetry, in transmission as in reflection, sufficiently neutral to not inconvenience the users or alternatively a slightly blue or green tint, in particular in the field of the building. These coatings are conventionally deposited by deposition techniques of the CVD type for the simplest or most often at present by deposition techniques by vacuum spraying, often called magnetron in the field, in particular when the coating is consisting of a more complex stack of successive layers.

Most often, the stacks in thin layers having solar control properties comprise one or even several active layers. By active or still functional layer is meant a layer which acts appreciably on the flow of solar or thermal radiation passing through said glazing. Such an active layer, in a known manner, can operate either mainly in the mode of reflection of the incident infrared radiation, or mainly in the mode of absorption of the incident infrared radiation.

In particular, the most efficient stacks marketed at present incorporate at least one metallic layer of the silver type operating essentially on the mode of reflection of a major part of the incident IR (infrared) radiation. Strong reflection of the medium infrared radiation also gives the property of low emissivity. These layers are however very sensitive to humidity and are therefore exclusively used in double glazing, opposite 2 or 3 thereof to be protected from humidity. The stacks according to the invention do not include such layers of the Silver type (in particular gold, platinum, copper, aluminum).

Other metallic layers with sunscreen function have also been described in the field, comprising functional layers of the Nb, Ta or W type or nitrides of these metals, as described for example in application W001 / 21540. However, within such layers, the solar radiation is this time absorbed and / or reflected but in a not very selective manner, that is to say that the IR radiation (whose wavelength is between approximately 780 nm and 2500 nm) and visible radiation are also absorbed / reflected non-selectively. Such glazing thus has little or no selectivity, and generally has a high emissivity.

In a conventional manner in the field of insulating glazing, selectivity is most often expressed as the ratio between the Light Transmission factor and the solar factor g (or FS). These quantities are in particular defined in standard NF EN 410.

In known and conventional manner, the light transmission factor or light transmission T _L corresponds to the percentage of the incident light flux, that is to say in the range of wavelengths 380 to 780 nm, passing through the glazing, depending on the illuminant D ₆₅ .

In known manner the solar factor g is it equal to the ratio of the energy passing through the glazing (that is to say entering the room) and the incident solar energy. More particularly, it corresponds to the sum of the flux transmitted directly through the glazing and the flux absorbed by the glazing (including the stacks of layers possibly present at one of its surfaces) then possibly re-emitted inward (the local).

In general, all the light characteristics presented in this description are obtained according to the principles and methods described in European (and French) standard EN 410 relating to the determination of the light and solar characteristics of the glazing used in glass for construction.

The object of the present invention is thus to provide glazing comprising a stack of layers giving them sunscreen properties, but also low emissivity properties, in particular a normal emissivity less than 0.5, or even less than 0.4 and having a high selectivity, in the sense described above, that is to say an optimized T _L / g ratio, in particular greater than 1, said stack being durable over time without any particular precautions.

By emissivity is meant normal emissivity and as measured in appendix A of standard ISO 10292 (1994).

A glazing unit according to the invention thus advantageously makes it possible to select the radiation passing through it, by promoting the transmission of light waves in the visible range, that is to say the wavelength of which is between approximately 380 and 780 nm , by selectively absorbing and / or reflecting the majority of infrared radiation, that is to say the wavelength of which is greater than 780 nm, in particular near infrared, that is to say the length of which d he wave is between about 780nm and about 3000nm, and by reflecting the average infrared, from 3 pm to 50 pm.

According to a first aspect of the invention, it is thus possible to maintain a high level of illumination of the room or of the passenger compartment protected by the glazing while minimizing the amount of heat entering it.

According to another aspect of the invention, it is thus possible to limit the radiative transfers between the interior and the exterior of the room or of the passenger compartment by proposing glazing whose emissivity is low.

According to another optional aspect of the present invention, it is sought to provide sunscreen glazing, said stack of which confers on said glazing a color in transmission and in substantially neutral external reflection or even a light blue-green tint, as sought in particular in the sector. of the building.

By neutral color is meant within the meaning of the present invention, in the colorimetry system (L *, a *, b *), b * values and a * values close to zero, in particular less than 10, or even less to 5, in absolute values.

By blue-green color is meant within the meaning of the present invention, in the colorimetry system (L *, a *, b *), negative b * values, in particular less than -10, or even less than -15 and values a * close to zero, in particular less than 10, or even less than 5, in absolute values.

In the case where the sunscreen glazing according to the invention is a laminated glazing in the sense described above, it also becomes possible to obtain neutral colors, in particular whose values of the parameters a * and b * are less than 5, in values absolute.

In particular, the applicant company has discovered that such objectives could be achieved by the use on glass substrates of stacks of layers including all the functional layers, that is to say all the layers of the reflective stack / absorbing most of the infrared solar radiation, are titanium oxynitride layers. Very particularly, according to the invention, it has been found very good emissivity and selectivity values, in the sense described above, could be obtained in such stacks thanks to the action of such layers, for oxygen levels and controlled nitrogen and as described below. In particular, while oxygen is considered in the art as an impurity which greatly affects the energetic properties of the functional layers of the nitride type, it has been found that very good selectivities and emissivities could be obtained for compounds comprising very precise proportions. elements Ti, 0, and N.

More specifically, the present invention relates to a glass article with an antisun function comprising at least one glass substrate and a stack of layers deposited on at least one face of said substrate, said stack of layers comprising a layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <

1.20 and in which 0.01 <y <0.10, said stack of layers further consisting of layers of dielectric materials and optionally of metal layers based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said metal layers being optionally nitrided.

By dielectric material is meant any material whose massive form devoid of impurities has a resistivity initially greater than 10 ohms-meters (Ω .m). Such materials, once deposited in thin layers, may however include additional elements significantly increasing their electrical conductivity, useful in particular for improving the sputtering efficiency of the precursor material constituting the magnetron target. For example, layers of silicon nitride used in the stack according to the invention can comprise a small amount of aluminum, the target of metallic silicon conventionally used during sputtering comprising for example in general from 6 to 10% by weight. aluminum, to increase the conductivity.

According to preferred embodiments of the present invention, which can optionally be combined with one another:

- In the glass article, 0.02 <y <0.08.

- In the glass article, 1.05 <x <1.20.

- The thickness of said layer of titanium oxynitride is between 10 and 80 nanometers, in particular between 15 and 60 nanometers, and very particularly between 15 and 50 nanometers.

- The stack also incorporates, below and / or above the layer of titanium oxynitride, one or more layers of dielectric materials.

- The dielectric material (s) are chosen from silicon nitride optionally doped with Al, Zr, B, aluminum nitride, tin oxide, a mixed zinc or tin oxide Sn _y Zn _z O _x , silicon oxide, titanium oxide, silicon oxynitrides SiO _x N _y .

- The stack also incorporates, below, and / or possibly above, the layer of titanium oxynitride, a layer of a metal, optionally partially or completely oxidized and / or nitrided, said metal being based chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably of thickness of less than 3 nm.

- The metal is chosen from Ti, Nb or an alloy of nickel and chromium, said metal or alloy being optionally nitrided. In particular, the metal is an alloy of nickel and chromium, possibly nitrided.

- The stack comprises or consists of the succession of the following layers, starting from the surface of the glass substrate:

a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm,

- optionally a layer of a metal, optionally partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably less than 3 nm,

said layer of titanium oxynitride of general formula TiN _x O _y , of thickness between 10 and 80 nm, preferably between 15 and 60 nanometers, and more preferably between 15 and 50 nanometers

- optionally a layer of a metal, optionally partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness less than 6 nm, preferably less than 3 nm,

- a layer of silicon nitride base thickness, between and nm, preferably between 25 and 70 nm

- optionally an upper layer based on a titanium oxide, a zirconium oxide or a titanium and zirconium oxide.

- The stack comprises or consists of the succession of the following layers, starting from the surface of the glass substrate:

a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm,

- A first layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <

1.20 and in which 0.01 <y <0.10, of thickness between 10 and 80 nm, preferably between 20 and 60 nanometers, and more preferably between 30 based on silicon nitride, and 80 nm , based on silicon nitride, and 80 nm, from and 50 nanometers,

a layer with a thickness between 20 preferably between 25 and 70 nm,

a second layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <

1.20 and in which 0.01 <y <0.10, of thickness between 10 and 80 nm, preferably between 20 and 60 nanometers, and more preferably between 30 and 50 nanometers,

a layer with a thickness between 20 preferably between 25 and 70 nm,

- optionally an upper layer based on a titanium oxide, a zirconium oxide or a titanium and zirconium oxide,

a layer of a metal, possibly partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably less than 3 nm, being optionally disposed between a layer of titanium oxynitride and a layer based on silicon nitride.

- Said article is a glazing comprising only one glass substrate.

- Said article has undergone a heat treatment such as quenching, bending or even annealing.

- Said article is a laminated glazing constituted by a set of at least two glass substrates linked together by a thermoplastic sheet, in particular of polyvinyl butyral (PVB).

The examples which follow are given purely by way of illustration and do not limit the scope of the present invention in any of the aspects described. For comparison purposes, all the stacks of the examples which follow are synthesized on glass substrates mounted in single glazing.

All the layers of the stacks were deposited according to conventional vacuum deposition techniques by magnetron sputtering.

Example 1:

In this example according to the invention, a stack consisting of the following sequence of layers was deposited, according to conventional magnetron techniques, on a glass substrate of the Planilux® type:

Glass / Si ₃ N ₄ / TiN _x O _y / Si ₃ N ₄ (31nm) (19nm) (2 9nm)

The TiN _x O _y layer is obtained by the magnetron sputtering technique from a metallic titanium target in an atmosphere essentially of nitrogen and argon, but containing an amount of oxygen of the order of 2%. in volume.

The silicon nitride layers are deposited according to conventional techniques in the field, from a silicon target comprising 8% by weight of aluminum in an atmosphere of nitrogen and argon.

In the following table, the main characteristics of the deposition process are reported:

Line speed (m / min) 1.7 If ₃ N ₄ Power on cathode (kW) 64 Pressure (pbar) 4 Ar flow (sccm) 700 Flux N ₂ (sccm) 850 TiN _x O _y Power (kW) 87 Pressure (pbar) 6 Ar flow (sccm) 1600 Flux N ₂ + 0 ₂ (sccm) 500 If ₃ N ₄ Power (kW) 78 Pressure (pbar) 4 Ar flow (sccm) 700 Flux N ₂ (sccm) 850

According to the invention, the glazing thus obtained is used as simple glazing or as the first substrate for obtaining a laminated glazing by laminating with another glass substrate of the Planilux® type using a sheet of PVB, l stack being disposed between the two glass substrates in the final glazing.

On the single glazing and the laminated glazing thus obtained, the factors T _L and g were measured in order to determine their selectivity. The results are reported in Table 1. Their colorimetric properties were also measured below. The results are reported in Table 3 below.

Example 2 (comparative):

In this example, the procedure was identical to Example 1 and a substantially identical stack was obtained, except that the nitrogen flow rate in the spraying chamber was increased to 800 sccm, so as to increase the value of x.

As in Example 1, the glazing thus obtained is used as simple glazing or as the first substrate for obtaining laminated glazing by laminating with another glass substrate of the Planilux® type using a sheet of PVB, the stack being disposed between the two glass substrates in the final glazing.

On the single glazing and the laminated glazing thus obtained, the factors T _L and g were measured in order to determine their selectivity. The results are reported in Table 1.

Example 3 (according to the invention):

In this example according to the invention, a stack consisting of the following sequence of layers was deposited, according to conventional magnetron techniques, on a glass substrate of the Planilux® type:

Glass / Si ₃ N ₄ / TiN _x O _y / Si ₃ N ₄ (61nm) (39nm) (6 Onm)

The TiN _x O _y layer is obtained by magnetron sputtering from a metallic titanium target in a very essentially nitrogen and argon atmosphere, but containing a quantity of oxygen, of the order of 2% by volume. .

In the table which follows, the main characteristics of the deposition process are reported:

Line speed (m / min) 0.9 If ₃ N ₄ Power on cathode (kW) 80 Pressure (pbar) 4 Ar flow (sccm) 700 Flux N ₂ (sccm) 850 TiN _x O _y Power (kW) 97 Pressure (pbar) 6 Ar flow (sccm) 1600 Flux N ₂ + 0 ₂ (sccm) 500 If ₃ N ₄ Power (kW) 70 Pressure (pbar) 4 Ar flow (sccm) 700 Flux N ₂ (sccm) 850

As in Example 1, the glazing thus obtained is used as single glazing or as the first substrate for obtaining a laminated glazing by laminating with another glass substrate of the Planilux® type using a sheet of PVB, the stack being disposed between the two glass substrates in the final glazing.

On the single glazing and the laminated glazing thus obtained, the factors T _L and g were measured in order to determine their selectivity. The results are reported in Table 2. Their colorimetric properties were also measured below. The results are reported in Table 3 below.

Example 4 (comparative):

In this example, the procedure was identical to Example 3 and a substantially identical stack was obtained, with the exception that a greater quantity of oxygen, of the order of 5%, was introduced into the spraying chamber. by volume in the atmosphere mainly of nitrogen and argon.

As in the previous examples, the glazing thus obtained is used as simple glazing (S) or as the first substrate for obtaining laminated glazing (F) by laminating with another glass substrate of the Planilux® type by means of a PVB sheet, the stack being arranged between the two glass substrates in the final glazing.

On the single glazing and the laminated glazing thus obtained, the factors T _L and g were measured in order to determine their selectivity. The results are reported in Table 2.

Example 5 (comparative):

In this example, a glazing from the applicant company sold under the reference Cool-Lite ST120 was used, the stack of which comprises a layer of niobium nitride as reflective / absorbent layer of solar radiation, surrounded by two layers of silicon nitride.

On these glazings, the factors T _L and g were measured under the same conditions as above in order to determine the selectivity. The results are reported in Table 2.

As in Example 1, the glazing thus obtained is used as simple glazing (S) or as the first substrate for obtaining laminated glazing (F) by laminating with another glass substrate of the Planilux® type by means of 'a sheet of PVB, the stack being arranged between the two glass substrates in the final glazing.

On the single glazing and the laminated glazing thus obtained, the factors T _L and g were measured in order to determine their selectivity. The results are reported in Table 2.

The values of x and y in the titanium oxynitride layers are conventionally measured by XPS techniques (X-ray photoelectron spectrometry) on a Nova-Kratos device according to the following conditions:

CONDITIONS OF ANALYSIS:

Source: Al Ka monochromatized

300 Watts for particular spectra

Area analyzed: 110x110 pm ² (modeqspot)

Detection angle: normal (θ = 0 °)

Depth analyzed less than 10 nm in normal detection

ABRASION CONDITIONS:

Ions: Ar - 2.0 keV

Scanning: 3 x 3 mm ² centered on the analysis area

Abrasion cycles / time per cycle: 30 cycles of 1 minute.

The characteristics of the various glazings obtained for Examples 1 and 2, measured according to the standards specified above, are given in Table 1 which follows:

Example 1 Example 2 Glazing type S * p * S * p * Layer functional TiN _x O _y TiN _x O _y x 1, 16 1, 16 1.20 1.20 there 0.03 0.03 0.03 0.03 T _L (%) 49, 1 four hundred ninety seven 46, 7 48.6 g (%) 45, 8 44.9 45, 4 45.6 selectivity (TL / g) 1.07 1, 11 1.03 1.07 emissivity (%) 45 N / A. 45 N / A.

S: single glazing - F: laminated glazing N.A: not applicable

Table 1

Example 3 Example 4 Example 5 Glazing type S * p * S * p * S * p * Layer functional TiN _x O _y TiN _x O _y NbN x 1, 16 1, 16 1, 16 1, 16 N / A. N / A. there 0.03 0.03 0.1 0.1 N / A. N / A. T _L (%) 32.1 28.9 37, 8 34.3 21.0 21.0 g (%) 29.8 30.9 34, 7 34, 7 30.0 29.5 selectivity (TL / g) 1.08 0.93 1.09 0.99 0.70 0.71 emissivity (%) 26 N / A. 40 N / A. 64 N / A.

S: single glazing - F: laminated glazing N.A: not applicable

Table 2

The comparison of the data reported in Tables 1 and 2 shows that greater selectivity is obtained when the stack in question comprises a functional layer whose nitrogen content x is in accordance with the invention, as the comparison of the examples 1 and 2, while the best emissivity, that is to say the lowest, is obtained for lower oxygen levels, as shown by the comparison of examples 3 and

4. The present invention allows the optimization of these two parameters, high selectivity and low emissivity. In particular, the applicant company was able to show, through the examples reported in the present application, that in such layers of titanium oxynitride very precise control of the composition of said layer, in particular the values of x and y , optimized both the selectivity and the emissivity of the glazing.

The colorimetric characteristics of the glazing according to Example 1 and according to Example 3, in the international system (CIE L * b * a *), were also measured in transmission and in external reflection (external side).

The substrate provided with its stack was also subjected to a heat treatment consisting of heating at 650 ° C. for a few minutes followed by quenching. This treatment is representative of the conditions undergone by the glazing if it has to be toughened or even curved.

All the optical data are shown in Table 3 below:

Light transmission Reflection outer T _L g T _L / g a * _T b * _T -F-Lext 3- * Rext Ή L / Rext Example 1 Glazing simple 49, 1 45, 8 1.07 -2.2 -2.8 10.9 -2.2 -9.5 Glazing simple hardened 55.2 48.3 1.14 -2.4 0.9 12.9 -3.8 -13.2 Glazing laminated four hundred ninety seven 44, 9 1.11 -3.4 -2 10.9 0.9 -o i Example 3 Glazing simple 32.1 29.8 1.08 -2.9 8.8 21.3 -2.2 7.0 Glazing simple hardened 40, 4 33.2 1.2 -4.6 9.1 19, 7 4.0 -0.6 Glazing laminated 28, 9 30.9 0.93 -4.5 2.8 17.4 1.1 3.3

Table 3

The data reported in Table 3 show the ideal properties of colorimetry in transmission and in external reflection of glazing provided with the stacks according to the invention:

- In transmission the parameters a * _T and b * _T remain relatively low, ensuring a relatively neutral color in transmission.

- In reflection, the parameter a * _ext according to the glazings according to the invention, is relatively low and often negative, while the parameter b * is close to 0 for laminated glazings (neutral color in reflection) is strongly negative for the glazing simple according to Example 1, which ensures a blue color of the glazing as desired in external vision.

Such colorimetric properties therefore give rise to a neutral or blue-green color which is not very intense in glazing in transmission but especially in external reflection, as is currently sought in the building sector.

According to another advantage, the sunscreen stacks according to the present invention, the active layer or layers of which are based on a titanium oxynitride are extremely simple to manufacture, in particular by the technique of vacuum deposition by cathode sputtering known as magnetron.

In addition, additional durability tests have shown that such layers could be easily deposited on face 2 of a single glazing, without risk of degradation thereof, by chemical action (humidity) or by mechanical action (abrasion of the stack).

Claims (10)

1. Glassware with sunscreen function comprising at least one glass substrate and a stack of layers deposited on at least one face of said substrate, said stack of layers comprising a layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <1.20 and in which 0.01 <y <0.10, said stack of layers consisting of at least one such layer of titanium oxynitride and layers of dielectric materials, as well as optionally metal layers based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said metal layers being optionally nitrided. 2. Glassware according to which 1 'a 0.02 <y of the <0.08. claims preceding, in 3. Glassware according to 1 'a of the claims preceding, in which 1.05 <x <1.20. 4. Glassware according to 1 'a of the claims preceding, in which the thickness of said layer titanium oxynitride is between 10 and 80 nanometers, in particular between 15 and 60 nanometers, and very particularly between 15 and 50 nanometers. 5. Glass article according to one of the preceding claims, wherein the stack further incorporates, below and / or above the layer of titanium oxynitride, one or more layers of dielectric materials. 6. Glass article according to the preceding claim, in which the dielectric material or materials are chosen from silicon nitride optionally doped with Al, Zr, B, aluminum nitride, tin oxide, a mixed zinc oxide. or tin Sn _y Zn _z O _x , silicon oxide, titanium oxide, silicon oxynitrides SiO _x N _y . 7. Glass article according to one of the preceding claims, in which the stack also incorporates, below, and / or possibly above, the layer of titanium oxynitride, a layer of a metal, possibly partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably thickness less than 3 nm. 8. Glass article according to the preceding claim, wherein the metal is chosen from Ti, Nb or an alloy of nickel and chromium, said metal or alloy being optionally nitrided. 9. Glass article according to one of the preceding claims, in which the stack comprises or consists of the succession of the following layers, starting from the surface of the glass substrate: a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm, - optionally a layer of a metal, optionally partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably less than 3 nm, said layer of titanium oxynitride of general formula TiN _x O _y , of thickness between 10 and 80 nm, preferably between 15 and 60 nanometers, and more preferably between 15 and 50 nanometers - optionally a layer of a metal, optionally partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness less than 6 nm, preferably less than 3 nm, a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm - optionally an upper layer based on a titanium oxide, a zirconium oxide or a titanium and zirconium oxide. 10. Glass article according to one of the preceding claims, in which the stack comprises or consists of the succession of the following layers, starting from the surface of the glass substrate: a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm, a first layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <1.20 and in which 0.01 <y <0.10, of thickness between 10 and 80 nm , preferably between 20 and 60 nanometers, and more preferably between 30 and 50 nanometers, a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm, a second layer of titanium oxynitride of general formula TiN _x O _y , in which 1.00 <x <1.20 and in which 0.01 <y <0.10, of thickness between 10 and 80 nm , preferably between 20 and 60 nanometers, and more preferably between 30 and 50 nanometers, a layer based on silicon nitride, of thickness between 20 and 80 nm, preferably between 25 and 70 nm, - optionally an upper layer based on a titanium oxide, a zirconium oxide or a titanium and zirconium oxide, a layer of a metal, possibly partially or completely oxidized and / or nitrided, said metal being based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements, said layer having a thickness of less than 5 nm, preferably less than 3 nm, being optionally disposed between a layer of titanium oxynitride and a layer based on silicon nitride. 11. Glass article according to one of the preceding claims, wherein said article is a glazing comprising only a single glass substrate. 12. Glass article according to the preceding claim, wherein said article has undergone a heat treatment such as quenching, bending or even annealing. 13. Glass article according to one of claims 1 to 10, wherein said article is a laminated glazing constituted by a set of at least two glass substrates bonded thermoplastic, between them by a sheet in particular of polyvinyl butyral (PVB).